As part of an effort to develop exotic materials such as room-temperature superconductors, researchers at Princeton University (Princeton, NJ) and ETH Zurich (Zurich, Switzerland) have locked together photons so that they become fixed in place.1 Their goal is to build a physical system that directly simulates the behavior of certain quantum materials; the physical system would in essence be a specialized quantum computer (as opposed to a general-purpose quantum computer, which is much more difficult).
To build their machine, the researchers created a structure made of superconducting materials that contains 100 billion atoms engineered to act as a single "artificial atom." They placed the artificial atom close to a superconducting wire containing photons.
By the rules of quantum mechanics, the photons on the wire can become quantum-mechanically entangled with the artificial atom. Normally photons do not interact with each other, but in this system the researchers are able to create new behavior in which the photons begin to interact with each other in some ways like particles.
"In one mode of operation, light sloshes back and forth like a liquid; in the other, it freezes," says Darius Sadri, a Princeton postdoctoral researcher.
The current device is relatively small, with only two sites where an artificial atom is paired with a superconducting wire. But the researchers say that by expanding the device and the number of interactions, they can increase their ability to simulate more complex systems -- growing from the simulation of a single molecule to that of an entire material. In the future, the team plans to build devices with hundreds of sites with which they hope to observe exotic phases of light such as superfluids and insulators.
Source: http://www.princeton.edu/engineering/news/archive/?id=13459
REFERENCE:
1. J. Raftery et al., Phys. Rev. X (2014); doi: 10.1103/PhysRevX.4.031043